Way too much that is inaccurate. Russell was not swayed by Millerism and his doctrines do not come from that source. He admired Miller for forcing people to look at Bible prophecies, but there were others, some of whom Russell names, that came before and who were greater influences on him.
Wendell did not start the Second Adventists. Not even close. See Isaac Wellcome's history of the second adventists movement for details.
A minor point is that Sunderlin and Bender, who Russell sent to Britain and Ireland to circulate Food for Thinking Christians, were not colporteurs and were not called such. They were there to make business contacts and to arrange for the printing of the UK version of "Food."
The errors in this video are many, and though I may note more later, I have a paper to write due on Monday. So that's it for now.
On the roots of Russell's belief system, try this:
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Penton draws on Schulz and de Vienne's books. [Rachael de Vienne was my mom, just for clarity here. And yes, I'm a bit partisan] Their Separate Identity books are on Amazon and Lulu and other book sites. Mom and Schulz both held PhD's and Bruce Schulz is B. W. Schulz, PhD, FRHistS [Fellow of the Royal History Society]